char – My Programming Notes

Tag Archives: char

Python || Using If Statements & String Variables

May 29, 2013 admin No comments

As previously mentioned, you can use “int” and “float” to represent numbers, but what if you want to store letters? Strings help you do that.

==== SINGLE CHAR ====

This example will demonstrate a simple program using strings, which checks to see if the user entered the correctly predefined letter.





		
		
			#1 - Guess a letter
			
Python
			
			# =============================================================================
#    Author: Kenneth Perkins
#    Date:   May 29, 2013
#    Updated: Feb 16, 2021
#    Taken From: http://programmingnotes.org/
#    File:  char.py
#    Description: Demonstrates using char variables
# =============================================================================
def main():
    # declare variables
    userInput = ""  # this variable is a string
    letter = '' # this holds the individual character

    # get data from user
    userInput = input("Please try to guess the letter I am thinking of: ")

    # we only want to check the first character in the string,
    # so we get the letter at index zero and save it into its
    # own variable
    letter = userInput[0]

    # use an if statement to check equality.
    if ((letter == 'a') or (letter == 'A')):
        print("\nYou have guessed correctly!")
    else:
        print("\nSorry, that was not the correct letter I was thinking of..")

if __name__ == "__main__":
    main()
# http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
				
						# =============================================================================
#    Author: Kenneth Perkins
#    Date:   May 29, 2013
#    Updated: Feb 16, 2021
#    Taken From: http://programmingnotes.org/
#    File:  char.py
#    Description: Demonstrates using char variables
# =============================================================================
def main():
    # declare variables
    userInput = ""  # this variable is a string
    letter = '' # this holds the individual character
 
    # get data from user
    userInput = input("Please try to guess the letter I am thinking of: ")
 
    # we only want to check the first character in the string,
    # so we get the letter at index zero and save it into its
    # own variable
    letter = userInput[0]
 
    # use an if statement to check equality.
    if ((letter == 'a') or (letter == 'A')):
        print("\nYou have guessed correctly!")
    else:
        print("\nSorry, that was not the correct letter I was thinking of..")
 
if __name__ == "__main__":
    main()
# http://programmingnotes.org/

Notice in line 11 I declare the string data type, naming it “userInput.” I also initialized it as an empty variable. In line 23 I used an “If/Else Statement” to determine if the user entered value matches the predefined letter within the program. I also used the “OR” operator in line 23 to determine if the letter the user entered into the program was lower or uppercase. Try compiling the program simply using this
if (letter == 'a') as your if statement, and notice the difference.

The resulting code should give this as output

Please try to guess the letter I am thinking of: A You have guessed correctly!

==== CHECK IF LETTER IS UPPER CASE ====

This example is similar to the previous one, and will check if a user entered letter is uppercase.





		
		
			#2 - Is Input Uppercase?
			
Python
			
			# =============================================================================
#    Author: Kenneth Perkins
#    Date:   May 29, 2013
#    Updated: Feb 16, 2021
#    Taken From: http://programmingnotes.org/
#    File:  uppercase.py
#    Description: Demonstrates checking if a char variable is uppercase
# =============================================================================
def main():
    # declare variables
    userInput = ""  # this variable is a string
    letter = '' # this holds the individual character

    # get data from user
    userInput = input("Please enter an UPPERCASE letter: ")

    # get the 1st character in the string
    letter = userInput[0]

    # check to see if entered data falls between uppercase values
    if ((letter >= 'A') and (letter <= 'Z')):
        print("\n'%c' is an is an uppercase letter!" % (letter))
    else:
        print("\nSorry, '%c' is not an uppercase letter.." % (letter))

if __name__ == "__main__":
    main()
# http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
				
						# =============================================================================
#    Author: Kenneth Perkins
#    Date:   May 29, 2013
#    Updated: Feb 16, 2021
#    Taken From: http://programmingnotes.org/
#    File:  uppercase.py
#    Description: Demonstrates checking if a char variable is uppercase
# =============================================================================
def main():
    # declare variables
    userInput = ""  # this variable is a string
    letter = '' # this holds the individual character
 
    # get data from user
    userInput = input("Please enter an UPPERCASE letter: ")
 
    # get the 1st character in the string
    letter = userInput[0]
 
    # check to see if entered data falls between uppercase values
    if ((letter >= 'A') and (letter <= 'Z')):
        print("\n'%c' is an is an uppercase letter!" % (letter))
    else:
        print("\nSorry, '%c' is not an uppercase letter.." % (letter))
 
if __name__ == "__main__":
    main()
# http://programmingnotes.org/

Notice in line 21, an If statement was used, which checks to see if the user entered data falls between letter A and letter Z. We did that by using the “AND” operator. So that IF statement is basically saying (in plain english)

IF ('letter' is equal to or greater than 'A') AND ('letter' is equal to or less than 'Z')
THEN it is an uppercase letter

The resulting code should give this as output

Please enter an UPPERCASE letter: g Sorry, 'g' is not an uppercase letter..

==== CHECK IF LETTER IS A VOWEL ====

This example will utilize more if statements, checking to see if the user entered letter is a vowel or not. This will be very similar to the previous example, utilizing the OR operator once again.





		
		
			#3 - Is Input a Vowel?
			
Python
			
			# =============================================================================
#    Author: Kenneth Perkins
#    Date:   May 29, 2013
#    Updated: Feb 16, 2021
#    Taken From: http://programmingnotes.org/
#    File:  vowel.py
#    Description: Demonstrates checking if a char variable is a vowel
# =============================================================================
def main():
    # declare variables
    userInput = ""  # this variable is a string
    letter = '' # this holds the individual character

    # get data from user
    userInput = input("Please enter a vowel: ")

    # get the 1st character in the string
    letter = userInput[0]

    # check to see if entered data is A,E,I,O,U,Y
    if ((letter == 'a')or(letter == 'A')or(letter == 'e')or
        (letter == 'E')or(letter == 'i')or(letter == 'I')or
        (letter == 'o')or(letter == 'O')or(letter == 'u')or
        (letter == 'U')or(letter == 'y')or(letter == 'Y')):
        print("\nCorrect, '%c' is a vowel!" % (letter))
    else:
        print("\nSorry, '%c' is not a vowel.." % (letter))

if __name__ == "__main__":
    main()
# http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
				
						# =============================================================================
#    Author: Kenneth Perkins
#    Date:   May 29, 2013
#    Updated: Feb 16, 2021
#    Taken From: http://programmingnotes.org/
#    File:  vowel.py
#    Description: Demonstrates checking if a char variable is a vowel
# =============================================================================
def main():
    # declare variables
    userInput = ""  # this variable is a string
    letter = '' # this holds the individual character
 
    # get data from user
    userInput = input("Please enter a vowel: ")
 
    # get the 1st character in the string
    letter = userInput[0]
 
    # check to see if entered data is A,E,I,O,U,Y
    if ((letter == 'a')or(letter == 'A')or(letter == 'e')or
        (letter == 'E')or(letter == 'i')or(letter == 'I')or
        (letter == 'o')or(letter == 'O')or(letter == 'u')or
        (letter == 'U')or(letter == 'y')or(letter == 'Y')):
        print("\nCorrect, '%c' is a vowel!" % (letter))
    else:
        print("\nSorry, '%c' is not a vowel.." % (letter))
 
if __name__ == "__main__":
    main()
# http://programmingnotes.org/

This program should be very straight forward, and its basically checking to see if the user entered data is the letter A, E, I, O, U or Y.

The resulting code should give the following output

Please enter a vowel: K Sorry, 'K' is not a vowel..

==== HELLO WORLD v2 ====

This last example will demonstrate using the string data type to print the line “Hello World!” to the screen.





		
		
			#4 - Hello World - String Version
			
Python
			
			# =============================================================================
#    Author: Kenneth Perkins
#    Date:   May 29, 2013
#    Updated: Feb 16, 2021
#    Taken From: http://programmingnotes.org/
#    File:  string.py
#    Description: Demonstrates using string variables
# =============================================================================
def main():
    # declare variables
    userInput = ""  # this variable is a string

    # get data from user
    userInput = input("Please enter a sentence: ")

    # display string
    print("\nYou Entered: '%s'" % (userInput))

if __name__ == "__main__":
    main()
# http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
				
						# =============================================================================
#    Author: Kenneth Perkins
#    Date:   May 29, 2013
#    Updated: Feb 16, 2021
#    Taken From: http://programmingnotes.org/
#    File:  string.py
#    Description: Demonstrates using string variables
# =============================================================================
def main():
    # declare variables
    userInput = ""  # this variable is a string
 
    # get data from user
    userInput = input("Please enter a sentence: ")
 
    # display string
    print("\nYou Entered: '%s'" % (userInput))
 
if __name__ == "__main__":
    main()
# http://programmingnotes.org/

The following is similar to the other examples listed on this page, except we display the entire string instead of just simply the first character.

The resulting code should give following output

Please enter a sentence: Hello World! You Entered: 'Hello World!'

C++ || Convert Numbers To Words Using A Switch Statement

July 21, 2012 admin No comments

This program demonstrates more practice using arrays and switch statements.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Integer Arrays Cin.get Isdigit For loops While Loops Switch Statements - How To Use

Using “cin.get(),” this program first asks the user to enter in a number (one at a time) that they wish to translate into words. If the text which was entered into the system is a number, the program will save the user input into an integer array. If the text is not a number, the input is discarded. After integer data is obtained, a for loop is used to traverse the integer array, passing the data to a switch statement, which translates the number to text.

This program is very simple, so it does not have the ability to display any number prefixes. As a result, if the number “1858” was entered into the system, the program would output the converted text: “One Eight Five Eight.”





		
		
			Convert Numbers To Words
			
C++
			
			#include <iostream>
#include <cctype>
using namespace std;
 
int main()
{
	// declare variables
	int numberArry[50];
	int numElems=0;
	char singleNum=' ';

	// ask the user for a number
	cout<<"Enter number: ";

	// get data from the user, one character at a time
	while(cin.get(singleNum) && singleNum != 'n')
	{
		// only numbers will be saved into the array, everything
		// else is ignored
		if(isdigit(singleNum))
		{
			// this converts a char into an integer using ascii values
			numberArry[numElems] = (singleNum)-'0'; 
			++numElems;
		}
	}

	cout<<endl;

	// using the data from the array, display the
	// numbers to the screen using a switch statement
	for(int index=0; index < numElems; ++index)
	{
		switch(numberArry[index])
		{
			case 0 :
				cout<<"Zero ";
				break;
			case 1 : 
				cout<<"One ";
				break;
			case 2: 
				cout<<"Two ";
				break;
			case 3: 
				cout<<"Three ";
				break;
			case 4:
				cout<<"Four ";
				break;
			case 5:
				cout<<"Five ";
				break;
			case 6:
				cout<<"Six ";
				break;
			case 7:
				cout<<"Seven ";
				break;
			case 8:
				cout<<"Eight ";
				break;
			case 9:
				cout<<"Nine ";
				break;
			default:
				cout<<"nERROR!n";
				break;
		}
	}
	cout<<endl;

	return 0;
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
				
						#include <iostream>
#include <cctype>
using namespace std;
 
int main()
{
	// declare variables
	int numberArry[50];
	int numElems=0;
	char singleNum=' ';
 
	// ask the user for a number
	cout<<"Enter number: ";
 
	// get data from the user, one character at a time
	while(cin.get(singleNum) && singleNum != 'n')
	{
		// only numbers will be saved into the array, everything
		// else is ignored
		if(isdigit(singleNum))
		{
			// this converts a char into an integer using ascii values
			numberArry[numElems] = (singleNum)-'0'; 
			++numElems;
		}
	}
 
	cout<<endl;
 
	// using the data from the array, display the
	// numbers to the screen using a switch statement
	for(int index=0; index < numElems; ++index)
	{
		switch(numberArry[index])
		{
			case 0 :
				cout<<"Zero ";
				break;
			case 1 : 
				cout<<"One ";
				break;
			case 2: 
				cout<<"Two ";
				break;
			case 3: 
				cout<<"Three ";
				break;
			case 4:
				cout<<"Four ";
				break;
			case 5:
				cout<<"Five ";
				break;
			case 6:
				cout<<"Six ";
				break;
			case 7:
				cout<<"Seven ";
				break;
			case 8:
				cout<<"Eight ";
				break;
			case 9:
				cout<<"Nine ";
				break;
			default:
				cout<<"nERROR!n";
				break;
		}
	}
	cout<<endl;
 
	return 0;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output
Note: The code was compiled four separate times to display different output

======= Run #1 =======
Enter number: 77331 Seven Seven Three Three One ======= Run #2 ======= Enter number: 234-43-1275 Two Three Four Four Three One Two Seven Five ======= Run #3 ======= Enter number: 1(800) 123-5678 One Eight Zero Zero One Two Three Five Six Seven Eight ======= Run #4 ======= Enter number: This 34 Is 24 A 5 Number 28
Three Four Two Four Five Two Eight

C++ || Char Array – Determine If A String Is A Number Or Not

May 24, 2012 admin No comments

The following is another intermediate homework assignment which was presented in a C++ programming course. This program was assigned to introduce more practice using and manipulating character arrays.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Character Arrays Cin.getline Strlen - Get The Length Of A Char Array Isalpha Isspace

This program first prompts the user to input a line of text. After it obtains data from the user, using a for loop, it then displays the the string to the screen one letter (char) at a time. If the current character at that specific array index is a letter, a “flag” is set, indicating that the current word which is being displayed is not a number. If the “flag” is not set, the current word is indeed a number.

This program has the ability to intake multiple words at a time, so for example, if the user input was “Hello World 2012” the program would display the output:

Hello is NOT a number! World is NOT a number! 2012 is a number..





		
		
			Determine If A String Is A Number Or Not
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 24, 2012
//    Taken From: http://programmingnotes.org/
//    File:  isNumber.cpp
//    Description: Demonstrates checking if a char array is a number
// ============================================================================
#include <iostream>
#include <cstring>
#include <cctype>
using namespace std;

// function prototype
void IsArryANum(char arry[]);

int main()
{
    // declare & initialize variables
    char arry[256];

    // obtain data from user
    cout << "Enter some text to see if its a number or not: "; 
    cin.getline(arry, sizeof(arry)); // getting line
    
    cout<<endl;         
    IsArryANum(arry);

    return 0;
}// end of main

void IsArryANum(char arry[])
{
    int notANumber = 0;
    int length = strlen(arry);
    
    // get the length of the char array
    // and place a [space] at the end of it. Then
    // set the array index after the [space] to NULL    
    arry[length] = ' ';
    arry[length + 1] = '\0';
    
    // increment the length to account for the space we just added
    ++length;
    
    for(int x = 0; x < length; ++x)
    {       
        cout <<arry[x]; // display the char at the current index

        // if the current char isnt a number, increment counter
        if(isalpha(arry[x])) 
        {
            ++notANumber;
        }
        // if curerent char is a space, that indicates we are 
        // at the end of the current word, so we 
        // display the results to the user
        else if(isspace(arry[x])) 
        {
            if (notANumber > 0)
            {               
                cout <<"is NOT a number!"
                    <<" There are "<<notANumber<<" letters"
                    <<" in that word...\n";
            }           
            else
            {
                cout <<"is a number..\n";
            }
            notANumber = 0;
        }
    }
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
				
						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 24, 2012
//    Taken From: http://programmingnotes.org/
//    File:  isNumber.cpp
//    Description: Demonstrates checking if a char array is a number
// ============================================================================
#include <iostream>
#include <cstring>
#include <cctype>
using namespace std;
 
// function prototype
void IsArryANum(char arry[]);
 
int main()
{
    // declare & initialize variables
    char arry[256];
 
    // obtain data from user
    cout << "Enter some text to see if its a number or not: "; 
    cin.getline(arry, sizeof(arry)); // getting line
    
    cout<<endl;         
    IsArryANum(arry);
 
    return 0;
}// end of main
 
void IsArryANum(char arry[])
{
    int notANumber = 0;
    int length = strlen(arry);
    
    // get the length of the char array
    // and place a [space] at the end of it. Then
    // set the array index after the [space] to NULL    
    arry[length] = ' ';
    arry[length + 1] = '\0';
    
    // increment the length to account for the space we just added
    ++length;
    
    for(int x = 0; x < length; ++x)
    {       
        cout <<arry[x]; // display the char at the current index
 
        // if the current char isnt a number, increment counter
        if(isalpha(arry[x])) 
        {
            ++notANumber;
        }
        // if curerent char is a space, that indicates we are 
        // at the end of the current word, so we 
        // display the results to the user
        else if(isspace(arry[x])) 
        {
            if (notANumber > 0)
            {               
                cout <<"is NOT a number!"
                    <<" There are "<<notANumber<<" letters"
                    <<" in that word...\n";
            }           
            else
            {
                cout <<"is a number..\n";
            }
            notANumber = 0;
        }
    }
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output
(Note: the code was compiled three separate times to display different output)

====== RUN 1 ======
Enter some text to see if its a number or not: My Programming Notes My is NOT a number! There are 2 letters in that word... Programming is NOT a number! There are 11 letters in that word... Notes is NOT a number! There are 5 letters in that word... ====== RUN 2 ====== Enter some text to see if its a number or not: May 30th 2012 May is NOT a number! There are 3 letters in that word... 30th is NOT a number! There are 2 letters in that word... 2012 is a number.. ====== RUN 3 ====== Enter some text to see if its a number or not: 5 31 2012
5 is a number.. 31 is a number.. 2012 is a number..

C++ || Snippet – How To Read & Write Data From A User Specified Text File

April 29, 2012 admin No comments

This page will consist of a demonstration of a simple quadratic formula program, which highlights the use of the input/output mechanisms of manipulating a text file. This program is very similar to an earlier snippet which was presented on this site, but in this example, the user has the option of choosing which file they want to manipulate. This program also demonstrates how to read in data from a file (numbers), manipulate that data, and output new data into a different text file.

REQUIRED KNOWLEDGE FOR THIS SNIPPET

Fstream Ifstream Ofstream Working With Files C_str() - Convert A String To Char Array Equivalent Getline - String Version

Note: The data file that is used in this example can be downloaded here.

Also, in order to read in the data .txt file, you need to save the .txt file in the same directory (or folder) as your .cpp file is saved in. If you are using Visual C++, this directory will be located in

Documents > Visual Studio 2010 > Projects > [Your project name] > [Your project name]





		
		
			User Specified Input/Output Manipulation
			
C++
			
			#include <iostream>
#include <fstream>
#include <string>
#include <cmath>
#include <cstdlib>
using namespace std;

int main() 
{
    // declare variables
    // char fileName[80];
    string fileName;    
    ifstream infile;
    ofstream outfile;
    double a=0,b=0,c=0;
    double root1=0, root2=0;    
    
    // get the name of the file from the user
    cout << "Please enter the name of the file: ";    
    getline(cin, fileName);
    
    // ^ you could also use a character array instead
    // of a string. Your getline declaration would look
    // like this:
    // ---------------------------------------------
    // cin.getline(fileName,80);


    // this opens the input file
    // NOTE: you need to convert the string to a 
    // char array using the function "c_str()"
    infile.open(fileName.c_str());
    
    // ^  if you used a char array as the file name instead 
    // of a string, the declaration to open the file 
    // would look like this:
    // ---------------------------------------------
    // infile.open(fileName);
    
    // check to see if the file even exists, & if not then EXIT
    if(infile.fail())
    {
        cout<<"nError, the input file could not be found!n";
        exit(1);
    }
    
    // this opens the output file
    // if the file doesnt already exist, it will be created
    outfile.open("OUTPUT_Quadratic_programmingnotes_freeweq_com.txt");  
    
    // this loop reads in data until there is no more 
    // data contained in the file
    while(infile.peek() != EOF)
    {
        // this assigns the incoming data to the
        // variables 'a', 'b' and 'c'
        // NOTE: it is just like a cin >> statement
        infile>> a >> b>> c;

        // NOTE: if you want to read data into an array
        // your declaration would be like this
        // ------------------------------------ 
        // infile>> a[counter] >> b[counter] >> c[counter];
        // ++counter;
    }    
    
    // this does the quadratic formula calculations
    root1 = ((-b) + sqrt(pow(b,2) - (4*a*c)))/(2*a);
    root2 = ((-b) - sqrt(pow(b,2) - (4*a*c)))/(2*a);

    // this displays the numbers to screen via cout
    cout <<"For the numbersna = "<<a<<"nb = "<<b<<"nc = "<<c<<endl;
    cout <<"nroot 1 = "<<root1<<"nroot 2 = "<<root2<<endl;
     
    // this saves the data to the output file
    // NOTE: its almost exactly the same as the cout statement
    outfile <<"For the numbersna = "<<a<<"nb = "<<b<<"nc = "<<c<<endl;
    outfile <<"nroot 1 = "<<root1<<"nroot 2 = "<<root2<<endl;

    // close the input/output files once you are done using them
    infile.close();
    outfile.close();

    // stops the program from automatically closing
    cout<<"nPress ENTER to continue...";
    cin.get();

    return 0;
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
				
						#include <iostream>
#include <fstream>
#include <string>
#include <cmath>
#include <cstdlib>
using namespace std;
 
int main() 
{
    // declare variables
    // char fileName[80];
    string fileName;    
    ifstream infile;
    ofstream outfile;
    double a=0,b=0,c=0;
    double root1=0, root2=0;    
    
    // get the name of the file from the user
    cout << "Please enter the name of the file: ";    
    getline(cin, fileName);
    
    // ^ you could also use a character array instead
    // of a string. Your getline declaration would look
    // like this:
    // ---------------------------------------------
    // cin.getline(fileName,80);
 
 
    // this opens the input file
    // NOTE: you need to convert the string to a 
    // char array using the function "c_str()"
    infile.open(fileName.c_str());
    
    // ^  if you used a char array as the file name instead 
    // of a string, the declaration to open the file 
    // would look like this:
    // ---------------------------------------------
    // infile.open(fileName);
    
    // check to see if the file even exists, & if not then EXIT
    if(infile.fail())
    {
        cout<<"nError, the input file could not be found!n";
        exit(1);
    }
    
    // this opens the output file
    // if the file doesnt already exist, it will be created
    outfile.open("OUTPUT_Quadratic_programmingnotes_freeweq_com.txt");  
    
    // this loop reads in data until there is no more 
    // data contained in the file
    while(infile.peek() != EOF)
    {
        // this assigns the incoming data to the
        // variables 'a', 'b' and 'c'
        // NOTE: it is just like a cin >> statement
        infile>> a >> b>> c;
 
        // NOTE: if you want to read data into an array
        // your declaration would be like this
        // ------------------------------------ 
        // infile>> a[counter] >> b[counter] >> c[counter];
        // ++counter;
    }    
    
    // this does the quadratic formula calculations
    root1 = ((-b) + sqrt(pow(b,2) - (4*a*c)))/(2*a);
    root2 = ((-b) - sqrt(pow(b,2) - (4*a*c)))/(2*a);
 
    // this displays the numbers to screen via cout
    cout <<"For the numbersna = "<<a<<"nb = "<<b<<"nc = "<<c<<endl;
    cout <<"nroot 1 = "<<root1<<"nroot 2 = "<<root2<<endl;
     
    // this saves the data to the output file
    // NOTE: its almost exactly the same as the cout statement
    outfile <<"For the numbersna = "<<a<<"nb = "<<b<<"nc = "<<c<<endl;
    outfile <<"nroot 1 = "<<root1<<"nroot 2 = "<<root2<<endl;
 
    // close the input/output files once you are done using them
    infile.close();
    outfile.close();
 
    // stops the program from automatically closing
    cout<<"nPress ENTER to continue...";
    cin.get();
 
    return 0;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output

Please enter the name of the file: INPUT_Quadratic_programmingnotes_freeweq_com.txt
For the numbers a = 2 b = 4 c = -16 root 1 = 2 root 2 = -4
Press ENTER to continue...

C++ || Class & Input/Output – Display The Contents Of A User Specified Text File To The Screen

April 24, 2012 admin No comments

The following is another intermediate homework assignment which was presented in a C++ programming course. This program was assigned to introduce more practice using the class data structure, which is very similar to the struct data structure.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Header Files - How To Use Them Class - What Is It? How To Read Data From A File String - Getline Array - Cin.Getline Strcpy - Copy Contents Of An Array #Define

This program first prompts the user to input a file name. After it obtains a file name from the user, it then attempts to display the contents of the user specified file to the output screen. If the file could not be found, an error message appears. If the file is found, the program continues as normal. After the file contents finishes being displayed, a summary indicating the total number of lines which has been read is also shown to the screen.

This program was implemented into 3 different files (two .cpp files, and one header file .h). So the code for this program will be broken up into 3 sections, the main file (.cpp), the header file (.h), and the implementation of the functions within the header file (.cpp).

Note: The data file that is used in this example can be downloaded here.

Documents > Visual Studio 2010 > Projects > [Your project name] > [Your project name]

======== FILE #1 – Main.cpp ========





		
		
			File #1 - Main.cpp
			
C++
			
			// ============================================================================
// File: Main.cpp 
// ============================================================================
// This program tests the "CFileDisp" object.  It prompts the user for an input
// filename, then attempts to display the contents of that file to stdout.
// After the file contents have been displayed, a summary line indicating the
// total number of lines that have been displayed is written to stdout.
// ============================================================================
#include <iostream>
#include <fstream>
#include "CFileDisp.h"
using namespace std;

// ==== main ==================================================================
//
// ============================================================================

int main()
{
	CFileDisp       myFile;
	char            fname[MAX_LENGTH];
	int             numLines;
	
	// get the filename from the user
	cout << "Enter a filename: ";
	cin.getline(fname, MAX_LENGTH);
	
	// copy the user's filename into the file object
	myFile.SetFilename(fname);
	
	// have the object open the file
	myFile.OpenFile();
	
	// if all is good and well...
	if(myFile.IsValid()==true)
	{
		numLines = myFile.DisplayFileContents();
		
		// close the file
		myFile.CloseFile();
		
		// write how many lines were displayed to stdout
		cout << "nt*** Total lines displayed: " << numLines << endl;
	}
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
				
						// ============================================================================
// File: Main.cpp 
// ============================================================================
// This program tests the "CFileDisp" object.  It prompts the user for an input
// filename, then attempts to display the contents of that file to stdout.
// After the file contents have been displayed, a summary line indicating the
// total number of lines that have been displayed is written to stdout.
// ============================================================================
#include <iostream>
#include <fstream>
#include "CFileDisp.h"
using namespace std;
 
// ==== main ==================================================================
//
// ============================================================================
 
int main()
{
	CFileDisp       myFile;
	char            fname[MAX_LENGTH];
	int             numLines;
	
	// get the filename from the user
	cout << "Enter a filename: ";
	cin.getline(fname, MAX_LENGTH);
	
	// copy the user's filename into the file object
	myFile.SetFilename(fname);
	
	// have the object open the file
	myFile.OpenFile();
	
	// if all is good and well...
	if(myFile.IsValid()==true)
	{
		numLines = myFile.DisplayFileContents();
		
		// close the file
		myFile.CloseFile();
		
		// write how many lines were displayed to stdout
		cout << "nt*** Total lines displayed: " << numLines << endl;
	}
	
	return 0;
}// http://programmingnotes.org/

======== FILE #2 – CFileDisp.h ========

Remember, you need to name the header file the same as the #include from the Main.cpp file. This file contains the function declarations, but no implementation of those functions takes place here.





		
		
			File #2 - CFileDisp.h
			
C++
			
			// ============================================================================
// File: CFileDisp.h
// ============================================================================
// This is the header file which declares the objects which are used to open 
// a text file and display its contents to stdout.
// ============================================================================
#ifndef CFILE_DISP_HEADER
#define CFILE_DISP_HEADER

#include <fstream>
using namespace std;

#define MAX_LENGTH  256

class   CFileDisp
{
public:
	// constructor
	CFileDisp();
	
	// member functions
	void SetFilename(char  newFilename[]);
	/*  Purpose: Copy the user's filename into the file object */
	void OpenFile();
	/* Purpose: Open's the file which is specified by the user */
	bool IsValid();
	/* Purpose: Checks if the file exists. 
	   Post: Returns false if file cannot be found */
	int DisplayFileContents();
	/* Purpose: Display's the file contents to stdout
	   Post: Returns the total number of lines contained in the file */
	void CloseFile();
	/* Purpose: Closes the file */
	
	// destructor
	~CFileDisp();

private:
    bool            m_bIsValid;
    char            m_filename[MAX_LENGTH];
    ifstream        m_inFile;
};
#endif   // CFILE_DISP_HEADER // http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
				
						// ============================================================================
// File: CFileDisp.h
// ============================================================================
// This is the header file which declares the objects which are used to open 
// a text file and display its contents to stdout.
// ============================================================================
#ifndef CFILE_DISP_HEADER
#define CFILE_DISP_HEADER
 
#include <fstream>
using namespace std;
 
#define MAX_LENGTH  256
 
class   CFileDisp
{
public:
	// constructor
	CFileDisp();
	
	// member functions
	void SetFilename(char  newFilename[]);
	/*  Purpose: Copy the user's filename into the file object */
	void OpenFile();
	/* Purpose: Open's the file which is specified by the user */
	bool IsValid();
	/* Purpose: Checks if the file exists. 
	   Post: Returns false if file cannot be found */
	int DisplayFileContents();
	/* Purpose: Display's the file contents to stdout
	   Post: Returns the total number of lines contained in the file */
	void CloseFile();
	/* Purpose: Closes the file */
	
	// destructor
	~CFileDisp();
 
private:
    bool            m_bIsValid;
    char            m_filename[MAX_LENGTH];
    ifstream        m_inFile;
};
#endif   // CFILE_DISP_HEADER // http://programmingnotes.org/

======== FILE #3 – CFileDisp.cpp ========

This is the function implementation file for the CFileDisp.h class. This file can be named anything you wish as long as you #include “CFileDisp.h”





		
		
			File #3 - CFileDisp.cpp
			
C++
			
			// ============================================================================
// File: CFileDisp.cpp
// ============================================================================
// This file implements the functions which are declared in the CFileDisp
// class, which is located in CFileDisp.h
// ============================================================================
#include <iostream>
#include <cstring>
#include <string>
#include "CFileDisp.h"
using namespace std;

CFileDisp::CFileDisp()
{
	m_bIsValid = 0;
}// end of CFileDisp

void CFileDisp::SetFilename(char  newFilename[])
{
    strcpy(m_filename,newFilename);
}// end of SetFilename

void CFileDisp::OpenFile()
{
	m_inFile.open(m_filename);
}// end of OpenFile

bool CFileDisp::IsValid()
{
	if (m_inFile.fail())
	{
		cout << m_filename << " was not found...nn";
		return false;
	}
	else 
	{
		return true;
	}
}// end of IsValid

int CFileDisp::DisplayFileContents()
{
	int total=0;
	string inLine;
	
	cout << endl;
	
	while(getline(m_inFile, inLine))
	{
		cout << inLine << endl;
		++total;
	}	
	return total;
}// end of DisplayFileContents

void CFileDisp::CloseFile()
{
	m_inFile.close();
}//	end of CloseFile

// this is the destructor
CFileDisp::~CFileDisp()
{
	m_bIsValid = 0;
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
				
						// ============================================================================
// File: CFileDisp.cpp
// ============================================================================
// This file implements the functions which are declared in the CFileDisp
// class, which is located in CFileDisp.h
// ============================================================================
#include <iostream>
#include <cstring>
#include <string>
#include "CFileDisp.h"
using namespace std;
 
CFileDisp::CFileDisp()
{
	m_bIsValid = 0;
}// end of CFileDisp
 
void CFileDisp::SetFilename(char  newFilename[])
{
    strcpy(m_filename,newFilename);
}// end of SetFilename
 
void CFileDisp::OpenFile()
{
	m_inFile.open(m_filename);
}// end of OpenFile
 
bool CFileDisp::IsValid()
{
	if (m_inFile.fail())
	{
		cout << m_filename << " was not found...nn";
		return false;
	}
	else 
	{
		return true;
	}
}// end of IsValid
 
int CFileDisp::DisplayFileContents()
{
	int total=0;
	string inLine;
	
	cout << endl;
	
	while(getline(m_inFile, inLine))
	{
		cout << inLine << endl;
		++total;
	}	
	return total;
}// end of DisplayFileContents
 
void CFileDisp::CloseFile()
{
	m_inFile.close();
}//	end of CloseFile
 
// this is the destructor
CFileDisp::~CFileDisp()
{
	m_bIsValid = 0;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output





		
		
			Enter a filename: input_file_display_programmingnotes_freeweq_com.txt

346     130     982     90      656     117   595
415     948     126     4       558     571   87
42      360     412     721     463     47    119
441     190     985     214     509     2     571
77      81      681     651     995     93    74
310     9       995     561     92      14    288
466     664     892     8       766     34    639
151     64      98      813     67      834   369

                This is a line of text!

        *** Total lines displayed: 10
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
				
						Enter a filename: input_file_display_programmingnotes_freeweq_com.txt
 
346     130     982     90      656     117   595
415     948     126     4       558     571   87
42      360     412     721     463     47    119
441     190     985     214     509     2     571
77      81      681     651     995     93    74
310     9       995     561     92      14    288
466     664     892     8       766     34    639
151     64      98      813     67      834   369
 
                This is a line of text!
 
        *** Total lines displayed: 10

C++ || Char Array – Palindrome Checker Using A Character Array, ToUpper, Strlen, Strcpy, & Strcmp

February 26, 2012 admin No comments

The following is a palindrome checking program, which demonstrates more use of char array’s, ToUpper, Strlen, & Strcmp.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Character Arrays Cin.getline How to convert text in a char array from lower to uppercase How to reverse a character array Palindrome - What is it? Strlen Strcpy Strcmp While Loops For Loops Constant Variables Setw

Using a constant value, by default, this program first asks the user to enter 5 words and/or sentences that they want to compare for similarity. If the text which was entered into the program is a palindrome, the program will prompt a message to the user via cout. This program determines similarity by using the strcmp function, to compare two arrays together. This program also demonstrates how to reverse a character array, aswell as demonstrates how to convert all the text which was placed into the char array from lower to UPPERCASE.





		
		
			Palindrome Checker Using A Char Array
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Feb 26, 2012
//    Taken From: http://programmingnotes.org/
//    File:  palindrome.cpp
//    Description: Demonstrates a simple palindrome checker
// ============================================================================
#include <iostream>
#include <iomanip>
#include <cstdlib>
#include <cctype>
#include <cstring>
using namespace std;

// constant value
const int NUM_WORDS = 5;

// function prototypes
void ConvertAllToUpper(char wordsCopy[][30], char palindrome[][30]);
void ReverseCharArray(char palindrome[][30]);
void CheckIfPalindrome(char wordsCopy[][30], char palindrome[][30], char words[][30]);

int main()
{
    // declare variable
    // this is a 2-D char array, which by default, has 
    // the ability to hold 5 names, each 30 characters long
    char words[NUM_WORDS][30];
    char wordsCopy[NUM_WORDS][30];
    char palindrome[NUM_WORDS][30];

    // get data from user
    cout << "\tWelcome to the Palindrome Check System!\n";
    cout << "\nPlease enter " << NUM_WORDS << " word(s) to check for similarity:\n";
    for (int index = 0; index < NUM_WORDS; ++index)
    {
        cout << "\t#" << index + 1 << ": ";
        cin.getline(words[index], 30);
    }

    // copy the user input into the 'wordsCopy' &
    // 'palindrome' char array
    for (int index = 0; index < NUM_WORDS; ++index)
    {
        strcpy(wordsCopy[index], words[index]);
        strcpy(palindrome[index], words[index]);
    }

    // create a line seperator
    cout << endl;
    cout.fill('-');
    cout << left << setw(30) << "" << right << setw(30) << "" << endl;

    // re-display the input to the screen
    cout << "\nThis is what you entered into the system:\n";
    for (int index = 0; index < NUM_WORDS; ++index)
    {
        cout << "\tText #" << index + 1 << ": " << words[index] << endl;
    }

    // create a line seperator
    cout << endl;
    cout.fill('-');
    cout << left << setw(30) << "" << right << setw(30) << "" << endl;

    // function declaration
    // convert all the text contained in the 2 arrays to
    // UPPERCASE
    ConvertAllToUpper(wordsCopy, palindrome);

    // function declaration
    // reverses all the text contained inside the char array
    // to determine if it is a palindrome
    ReverseCharArray(palindrome);

    // display the palindrome's  to the screen
    cout << "\nHere are the palindrome's:\n";

    // function declaration
    // checks to see if the text contained in the char
    // array is a palindrome or not
    CheckIfPalindrome(wordsCopy, palindrome, words);

    cin.get();
    return 0;
}// end of main

void ConvertAllToUpper(char wordsCopy[][30], char palindrome[][30])
{
    int index = 0;

    // increment thru the current char array index
    while (index < NUM_WORDS)
    {
        // increment thru each letter within the current char array index
        for (unsigned currentChar = 0; currentChar < strlen(wordsCopy[index]); ++currentChar)
        {
            // checks each letter in the current array index
            // to see if its lower or UPPERCASE
            // if its lowercase, change to UPPERCASE
            if (islower(wordsCopy[index][currentChar]))
            {
                wordsCopy[index][currentChar] = toupper(wordsCopy[index][currentChar]);
                palindrome[index][currentChar] = toupper(palindrome[index][currentChar]);
            }
        }
        ++index;
    }
}// end of ConvertAllToUpper

void ReverseCharArray(char palindrome[][30])
{
    int index = 0;

    // increment thru the current char array index
    while (index < NUM_WORDS)
    {    // get the length of the current word in the array index
        int wordLength = strlen(palindrome[index]) - 1;
        // increment thru each letter within the current char array index
        // reversing the order of the array
        for (int currentChar = 0; currentChar < wordLength; --wordLength, ++currentChar)
        {
            // copy 1st letter in the array index into temp
            char temp = palindrome[index][currentChar];
            // copy last letter in the array index into the 1st array index
            palindrome[index][currentChar] = palindrome[index][wordLength];
            // copy temp into last array index
            palindrome[index][wordLength] = temp;
        }
        ++index;
    }
}// end of ReverseCharArray

void CheckIfPalindrome(char wordsCopy[][30], char palindrome[][30], char words[][30])
{
    int palindromeCount = 0;

    // increment thru the current char array index
    for (int index = 0; index < NUM_WORDS; ++index)
    {
        // if the contents in the 'wordsCopy' & 'palindrome'
        // are the same, then the word is a palindrome
        if (strcmp(wordsCopy[index], palindrome[index]) == 0)
        {
            cout << "\tText #" << index + 1 << ": " << words[index] << " is a palindrome" << endl;
            ++palindromeCount;
        }
    }
    if (palindromeCount == 0)
    {
        cout << "There were no palindrome's found in the current list!\n";
    }
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
				
						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Feb 26, 2012
//    Taken From: http://programmingnotes.org/
//    File:  palindrome.cpp
//    Description: Demonstrates a simple palindrome checker
// ============================================================================
#include <iostream>
#include <iomanip>
#include <cstdlib>
#include <cctype>
#include <cstring>
using namespace std;
 
// constant value
const int NUM_WORDS = 5;
 
// function prototypes
void ConvertAllToUpper(char wordsCopy[][30], char palindrome[][30]);
void ReverseCharArray(char palindrome[][30]);
void CheckIfPalindrome(char wordsCopy[][30], char palindrome[][30], char words[][30]);
 
int main()
{
    // declare variable
    // this is a 2-D char array, which by default, has 
    // the ability to hold 5 names, each 30 characters long
    char words[NUM_WORDS][30];
    char wordsCopy[NUM_WORDS][30];
    char palindrome[NUM_WORDS][30];
 
    // get data from user
    cout << "\tWelcome to the Palindrome Check System!\n";
    cout << "\nPlease enter " << NUM_WORDS << " word(s) to check for similarity:\n";
    for (int index = 0; index < NUM_WORDS; ++index)
    {
        cout << "\t#" << index + 1 << ": ";
        cin.getline(words[index], 30);
    }
 
    // copy the user input into the 'wordsCopy' &
    // 'palindrome' char array
    for (int index = 0; index < NUM_WORDS; ++index)
    {
        strcpy(wordsCopy[index], words[index]);
        strcpy(palindrome[index], words[index]);
    }
 
    // create a line seperator
    cout << endl;
    cout.fill('-');
    cout << left << setw(30) << "" << right << setw(30) << "" << endl;
 
    // re-display the input to the screen
    cout << "\nThis is what you entered into the system:\n";
    for (int index = 0; index < NUM_WORDS; ++index)
    {
        cout << "\tText #" << index + 1 << ": " << words[index] << endl;
    }
 
    // create a line seperator
    cout << endl;
    cout.fill('-');
    cout << left << setw(30) << "" << right << setw(30) << "" << endl;
 
    // function declaration
    // convert all the text contained in the 2 arrays to
    // UPPERCASE
    ConvertAllToUpper(wordsCopy, palindrome);
 
    // function declaration
    // reverses all the text contained inside the char array
    // to determine if it is a palindrome
    ReverseCharArray(palindrome);
 
    // display the palindrome's  to the screen
    cout << "\nHere are the palindrome's:\n";
 
    // function declaration
    // checks to see if the text contained in the char
    // array is a palindrome or not
    CheckIfPalindrome(wordsCopy, palindrome, words);
 
    cin.get();
    return 0;
}// end of main
 
void ConvertAllToUpper(char wordsCopy[][30], char palindrome[][30])
{
    int index = 0;
 
    // increment thru the current char array index
    while (index < NUM_WORDS)
    {
        // increment thru each letter within the current char array index
        for (unsigned currentChar = 0; currentChar < strlen(wordsCopy[index]); ++currentChar)
        {
            // checks each letter in the current array index
            // to see if its lower or UPPERCASE
            // if its lowercase, change to UPPERCASE
            if (islower(wordsCopy[index][currentChar]))
            {
                wordsCopy[index][currentChar] = toupper(wordsCopy[index][currentChar]);
                palindrome[index][currentChar] = toupper(palindrome[index][currentChar]);
            }
        }
        ++index;
    }
}// end of ConvertAllToUpper
 
void ReverseCharArray(char palindrome[][30])
{
    int index = 0;
 
    // increment thru the current char array index
    while (index < NUM_WORDS)
    {    // get the length of the current word in the array index
        int wordLength = strlen(palindrome[index]) - 1;
        // increment thru each letter within the current char array index
        // reversing the order of the array
        for (int currentChar = 0; currentChar < wordLength; --wordLength, ++currentChar)
        {
            // copy 1st letter in the array index into temp
            char temp = palindrome[index][currentChar];
            // copy last letter in the array index into the 1st array index
            palindrome[index][currentChar] = palindrome[index][wordLength];
            // copy temp into last array index
            palindrome[index][wordLength] = temp;
        }
        ++index;
    }
}// end of ReverseCharArray
 
void CheckIfPalindrome(char wordsCopy[][30], char palindrome[][30], char words[][30])
{
    int palindromeCount = 0;
 
    // increment thru the current char array index
    for (int index = 0; index < NUM_WORDS; ++index)
    {
        // if the contents in the 'wordsCopy' & 'palindrome'
        // are the same, then the word is a palindrome
        if (strcmp(wordsCopy[index], palindrome[index]) == 0)
        {
            cout << "\tText #" << index + 1 << ": " << words[index] << " is a palindrome" << endl;
            ++palindromeCount;
        }
    }
    if (palindromeCount == 0)
    {
        cout << "There were no palindrome's found in the current list!\n";
    }
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

Click here to see how cin.getline works.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output
(Note: The code was compiled 2 seperate times to demonstrate different output)

====== RUN 1 ======
Welcome to the Palindrome Check System! Please enter 5 word(s) to check for similarity: #1: SteP oN nO PEts #2: My ProGramminG NoTeS #3: RaTs liVE ON No eViL StaR #4: ABLe wAs I ErE I sAw ElBa #5: LiVE Non Evil ------------------------------------------------------------ This is what you entered into the system: Text #1: SteP oN nO PEts Text #2: My ProGramminG NoTeS Text #3: RaTs liVE ON No eViL StaR Text #4: ABLe wAs I ErE I sAw ElBa Text #5: LiVE Non Evil ------------------------------------------------------------ Here are the palindrome's: Text #1: SteP oN nO PEts is a palindrome Text #3: RaTs liVE ON No eViL StaR is a palindrome Text #4: ABLe wAs I ErE I sAw ElBa is a palindrome Text #5: LiVE Non Evil is a palindrome ====== RUN 2 ====== Welcome to the Palindrome Check System! Please enter 5 word(s) to check for similarity: #1: today Is Great #2: Tomorrow is Foriegn #3: Sunday Brunch #4: Hello SkiPper #5: Mayday Ship DowN! ------------------------------------------------------------ This is what you entered into the system: Text #1: today Is Great Text #2: Tomorrow is Foriegn Text #3: Sunday Brunch Text #4: Hello SkiPper Text #5: Mayday Ship DowN!
------------------------------------------------------------ Here are the palindrome's: There were no palindrome's found in the current list!

C++ || Char Array – Convert Text Contained In A Character Array From Lower To UPPERCASE

February 25, 2012 admin No comments

This program demonstrates how to switch text which is contained in a char array from lower to UPPERCASE. This program also demonstrates how to convert all of the text contained in a char array to lower/UPPERCASE.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Character Arrays Cin.getline Islower Isupper Tolower Toupper Strlen While Loops For Loops Constant Variables Setw

Using a constant integer value, this program first asks the user to enter in 3 lines of text they wish to convert from lower to UPPERCASE. Upon obtaining the information from the user, the program then converts all the text which was placed into the character array from lower to uppercase in the following order:

(1) Switches the text from lower to UPPERCASE (2) Converts all the text to UPPERCASE (3) Converts all the text to lowercase

After each conversion is complete, the program displays the updated information to the screen via cout.

NOTE: On some compilers, you may have to add #include < cstdlib>, #include < cctype>, and #include < cstring> in order for the code to compile.





		
		
			Convert Text From Lower To UPPERCASE
			
C++
			
			#include <iostream>
#include <iomanip>
using namespace std;

// constant value
const int NUM_NAMES = 3;

// function prototype
void ConvertLowerToUpper(char names[][30]);
void ConvertAllToUpper(char names[][30]);
void ConvertAllToLower(char names[][30]);

int main()
{
	// declare variable
	// this is a 2-D char array, which by default, has 
	// the ability to hold 3 names, each 30 characters long
	char names[NUM_NAMES][30];

	// get data from user
	cout << "Please enter "<<NUM_NAMES<<" line(s) of text you wish to convert from lower to UPPERCASE:nt";
	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"#"<< index+1 <<": ";
		cin.getline(names[index],30);
		cout<< "t";
	}

	// create a line seperator
	cout<<endl;
	cout.fill('-');
	cout<<left<<setw(30)<<""<<right<<setw(30)<<""<<endl; 

	// re-display the input to the screen
	cout << "nThis is what you entered into the system:nt";
	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"Text #"<< index+1 <<": "<<names[index]<<endl;
		cout<< "t";
	}
	
	// create a line seperator
	cout<<endl;
	cout.fill('-');
	cout<<left<<setw(30)<<""<<right<<setw(30)<<""<<endl; 

	// display the switched lower to UPPERCASE text to the user
	cout << "nThis is the information switched from lower to UPPERCASE:nt";
	
	// function declaration
	ConvertLowerToUpper(names);

	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"Text #"<< index+1 <<": "<<names[index]<<endl;
		cout<< "t";
	}

	// create a line seperator
	cout<<endl;
	cout.fill('-');
	cout<<left<<setw(30)<<""<<right<<setw(30)<<""<<endl; 

	// display the 'all UPPERCASE' converted text to the user
	cout << "nThis is the information converted to all UPPERCASE:nt";
	
	// function declaration
	ConvertAllToUpper(names);

	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"Text #"<< index+1 <<": "<<names[index]<<endl;
		cout<< "t";
	}

	// create a line seperator
	cout<<endl;
	cout.fill('-');
	cout<<left<<setw(30)<<""<<right<<setw(30)<<""<<endl; 

	// display the 'all lowercase' converted text to the user
	cout << "nThis is the information converted to all lowercase:nt";
	
	// function declaration
	ConvertAllToLower(names);

	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"Text #"<< index+1 <<": "<<names[index]<<endl;
		cout<< "t";
	}

	return 0;
}// end of main

void ConvertLowerToUpper(char names[][30])
{
	int index=0;

	// increment thru the current char array index
	while(index < NUM_NAMES)
	{
		// increment thru each letter within the current char array index
		for(int currentChar=0;  currentChar < strlen(names[index]); ++currentChar)
		{
			// checks each letter in the current array index
			// to see if its lower or UPPERCASE
			// if its lowercase, change to UPPERCASE
			if (islower(names[index][currentChar]))
			{
				names[index][currentChar] = toupper(names[index][currentChar]);
			}
			else  // if its UPPERCASE, change to lowercase
			{
				names[index][currentChar] = tolower(names[index][currentChar]);
			}
		}
		++index;
	}
}// end of ConvertLowerToUpper

void ConvertAllToUpper(char names[][30])
{
	int index=0;

	// increment thru the current char array index
	while(index < NUM_NAMES)
	{
		// increment thru each letter within the current char array index
		for(int currentChar=0;  currentChar < strlen(names[index]); ++currentChar)
		{
			// checks each letter in the current array index
			// to see if its lower or UPPERCASE
			// if its lowercase, change to UPPERCASE
			if (islower(names[index][currentChar]))
			{
				names[index][currentChar] = toupper(names[index][currentChar]);
			}
		}
		++index;
	}
}// end of ConvertAllToUpper

void ConvertAllToLower(char names[][30])
{
	int index=0;

	// increment thru the current char array index
	while(index < NUM_NAMES)
	{
		// increment thru each letter within the current char array index
		for(int currentChar=0;  currentChar < strlen(names[index]); ++currentChar)
		{
			// checks each letter in the current array index
			// to see if its lower or UPPERCASE
			// if its UPPERCASE, change to lowercase
			if (isupper(names[index][currentChar]))
			{
				names[index][currentChar] = tolower(names[index][currentChar]);
			}
		}
		++index;
	}
}// http://programmingnotes.org/ 
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
				
						#include <iostream>
#include <iomanip>
using namespace std;
 
// constant value
const int NUM_NAMES = 3;
 
// function prototype
void ConvertLowerToUpper(char names[][30]);
void ConvertAllToUpper(char names[][30]);
void ConvertAllToLower(char names[][30]);
 
int main()
{
	// declare variable
	// this is a 2-D char array, which by default, has 
	// the ability to hold 3 names, each 30 characters long
	char names[NUM_NAMES][30];
 
	// get data from user
	cout << "Please enter "<<NUM_NAMES<<" line(s) of text you wish to convert from lower to UPPERCASE:nt";
	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"#"<< index+1 <<": ";
		cin.getline(names[index],30);
		cout<< "t";
	}
 
	// create a line seperator
	cout<<endl;
	cout.fill('-');
	cout<<left<<setw(30)<<""<<right<<setw(30)<<""<<endl; 
 
	// re-display the input to the screen
	cout << "nThis is what you entered into the system:nt";
	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"Text #"<< index+1 <<": "<<names[index]<<endl;
		cout<< "t";
	}
	
	// create a line seperator
	cout<<endl;
	cout.fill('-');
	cout<<left<<setw(30)<<""<<right<<setw(30)<<""<<endl; 
 
	// display the switched lower to UPPERCASE text to the user
	cout << "nThis is the information switched from lower to UPPERCASE:nt";
	
	// function declaration
	ConvertLowerToUpper(names);
 
	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"Text #"<< index+1 <<": "<<names[index]<<endl;
		cout<< "t";
	}
 
	// create a line seperator
	cout<<endl;
	cout.fill('-');
	cout<<left<<setw(30)<<""<<right<<setw(30)<<""<<endl; 
 
	// display the 'all UPPERCASE' converted text to the user
	cout << "nThis is the information converted to all UPPERCASE:nt";
	
	// function declaration
	ConvertAllToUpper(names);
 
	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"Text #"<< index+1 <<": "<<names[index]<<endl;
		cout<< "t";
	}
 
	// create a line seperator
	cout<<endl;
	cout.fill('-');
	cout<<left<<setw(30)<<""<<right<<setw(30)<<""<<endl; 
 
	// display the 'all lowercase' converted text to the user
	cout << "nThis is the information converted to all lowercase:nt";
	
	// function declaration
	ConvertAllToLower(names);
 
	for(int index=0; index < NUM_NAMES; ++index)
	{
		cout<<"Text #"<< index+1 <<": "<<names[index]<<endl;
		cout<< "t";
	}
 
	return 0;
}// end of main
 
void ConvertLowerToUpper(char names[][30])
{
	int index=0;
 
	// increment thru the current char array index
	while(index < NUM_NAMES)
	{
		// increment thru each letter within the current char array index
		for(int currentChar=0;  currentChar < strlen(names[index]); ++currentChar)
		{
			// checks each letter in the current array index
			// to see if its lower or UPPERCASE
			// if its lowercase, change to UPPERCASE
			if (islower(names[index][currentChar]))
			{
				names[index][currentChar] = toupper(names[index][currentChar]);
			}
			else  // if its UPPERCASE, change to lowercase
			{
				names[index][currentChar] = tolower(names[index][currentChar]);
			}
		}
		++index;
	}
}// end of ConvertLowerToUpper
 
void ConvertAllToUpper(char names[][30])
{
	int index=0;
 
	// increment thru the current char array index
	while(index < NUM_NAMES)
	{
		// increment thru each letter within the current char array index
		for(int currentChar=0;  currentChar < strlen(names[index]); ++currentChar)
		{
			// checks each letter in the current array index
			// to see if its lower or UPPERCASE
			// if its lowercase, change to UPPERCASE
			if (islower(names[index][currentChar]))
			{
				names[index][currentChar] = toupper(names[index][currentChar]);
			}
		}
		++index;
	}
}// end of ConvertAllToUpper
 
void ConvertAllToLower(char names[][30])
{
	int index=0;
 
	// increment thru the current char array index
	while(index < NUM_NAMES)
	{
		// increment thru each letter within the current char array index
		for(int currentChar=0;  currentChar < strlen(names[index]); ++currentChar)
		{
			// checks each letter in the current array index
			// to see if its lower or UPPERCASE
			// if its UPPERCASE, change to lowercase
			if (isupper(names[index][currentChar]))
			{
				names[index][currentChar] = tolower(names[index][currentChar]);
			}
		}
		++index;
	}
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

Click here to see how cin.getline works.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output

Please enter 3 line(s) of text you wish to convert from lower to UPPERCASE: #1: I StriKe hiM a heAVy bloW. #2: When cAn the neRve ShinE? #3: My Programming Notes.
------------------------------------------------------------ This is what you entered into the system: Text #1: I StriKe hiM a heAVy bloW. Text #2: When cAn the neRve ShinE? Text #3: My Programming Notes. ------------------------------------------------------------ This is the information switched from lower to UPPERCASE: Text #1: i sTRIkE HIm A HEavY BLOw. Text #2: wHEN CaN THE NErVE sHINe? Text #3: mY pROGRAMMING nOTES. ------------------------------------------------------------ This is the information converted to all UPPERCASE: Text #1: I STRIKE HIM A HEAVY BLOW. Text #2: WHEN CAN THE NERVE SHINE? Text #3: MY PROGRAMMING NOTES.
------------------------------------------------------------ This is the information converted to all lowercase: Text #1: i strike him a heavy blow. Text #2: when can the nerve shine? Text #3: my programming notes.

C++ || Using If Statements, Char & String Variables

January 04, 2012 admin No comments

As previously mentioned, you can use the “int/float/double” data type to store numbers. But what if you want to store letters? Char and Strings help you do that.

==== SINGLE CHAR ====

This example will demonstrate a simple program using char, which checks to see if you entered the correctly predefined letter.





		
		
			Guess a letter
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 4, 2012
//    Updated: Feb 8, 2021
//    Taken From: http://programmingnotes.org/
//    File:  char.cpp
//    Description: Demonstrates using char variables
// ============================================================================
#include <iostream>
int main()
{
    // Declare empty variable
    char userInput = ' ';

    std::cout << "Please try to guess the letter I am thinking of: ";
    std::cin >> userInput;

    // Use an If Statement to check equality
    if (userInput == 'a' || userInput == 'A')
    {
        std::cout <<"\nYou have Guessed correctly!"<< std::endl;
    }
    else
    {
        std::cout <<"\nSorry, that was not the correct letter I was thinking of"<< std::endl;
    }
    return 0;
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
				
						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 4, 2012
//    Updated: Feb 8, 2021
//    Taken From: http://programmingnotes.org/
//    File:  char.cpp
//    Description: Demonstrates using char variables
// ============================================================================
#include <iostream>
int main()
{
    // Declare empty variable
    char userInput = ' ';
 
    std::cout << "Please try to guess the letter I am thinking of: ";
    std::cin >> userInput;
 
    // Use an If Statement to check equality
    if (userInput == 'a' || userInput == 'A')
    {
        std::cout <<"\nYou have Guessed correctly!"<< std::endl;
    }
    else
    {
        std::cout <<"\nSorry, that was not the correct letter I was thinking of"<< std::endl;
    }
    return 0;
}// http://programmingnotes.org/

Notice in line 13 I declare the char data type, naming it “userInput.” I also initialized it as an empty variable. In line 19 I used an “If/Else Statement” to determine if the user inputted value matches the predefined letter within the program. I also used the “OR” operator in line 19 to determine if the letter the user inputted was lower or uppercase. Try compiling the program simply using this
if (userInput == 'a') as your if statement, and notice the difference.

The resulting code should give this as output

Please try to guess the letter I am thinking of: K Sorry, that was not the correct letter I was thinking of

==== CHECK IF LETTER IS UPPER CASE ====

This example is similar to the previous one, and will check if a letter is uppercase.





		
		
			Is Input Uppercase?
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 4, 2012
//    Updated: Feb 8, 2021
//    Taken From: http://programmingnotes.org/
//    File:  uppercase.cpp
//    Description: Demonstrates checking if a char variable is uppercase
// ============================================================================
#include <iostream>
int main()
{
    // Declare empty variable
    char userInput = ' ';

    std::cout << "Please enter an UPPERCASE letter: ";
    std::cin >> userInput;

    // Checks to see if entered data falls between uppercase values
    if ((userInput >= 'A') && (userInput <= 'Z'))
    {
        std::cout << "\n" << userInput << " is an uppercase letter"<< std::endl;
    }
    else
    {
        std::cout <<"\nSorry, "<< userInput <<" is not an uppercase letter"<< std::endl;
    }
    return 0;
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
				
						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 4, 2012
//    Updated: Feb 8, 2021
//    Taken From: http://programmingnotes.org/
//    File:  uppercase.cpp
//    Description: Demonstrates checking if a char variable is uppercase
// ============================================================================
#include <iostream>
int main()
{
    // Declare empty variable
    char userInput = ' ';
 
    std::cout << "Please enter an UPPERCASE letter: ";
    std::cin >> userInput;
 
    // Checks to see if entered data falls between uppercase values
    if ((userInput >= 'A') && (userInput <= 'Z'))
    {
        std::cout << "\n" << userInput << " is an uppercase letter"<< std::endl;
    }
    else
    {
        std::cout <<"\nSorry, "<< userInput <<" is not an uppercase letter"<< std::endl;
    }
    return 0;
}// http://programmingnotes.org/

Notice in line 19, an If statement was used, which checked to see if the user entered data fell between letter A and letter Z. We did that by using the “AND” operator. So that IF statement is basically saying (in plain english)

IF ('userInput' is equal to or greater than 'A') AND ('userInput' is equal to or less than 'Z')
THEN it is an uppercase letter

C++ uses ASCII codes to determine letters, so from looking at the table, the letter ‘A’ would equal ASCII code number 65, letter ‘B’ would equal ASCII code number 66 and so forth, until you reach letter Z, which would equal ASCII code number 90. So in literal terms, the program is checking to see if the user input is between ASCII code number 65 thru 90. If it is, then the number is an uppercase letter, otherwise it is not.

The resulting code should give this as output

Please enter an UPPERCASE letter: G G is an uppercase letter

==== CHECK IF LETTER IS A VOWEL ====

This example will utilize more if statements, checking to see if the user inputted data is a vowel or not. This will be very similar to the previous example, utilizing the OR operator once again.





		
		
			Is Input a Vowel?
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 4, 2012
//    Updated: Feb 8, 2021
//    Taken From: http://programmingnotes.org/
//    File:  vowel.cpp
//    Description: Demonstrates checking if a char variable is a vowel
// ============================================================================
#include <iostream>
int main()
{
    // Declare empty variable
    char userInput = ' ';

    std::cout << "Please enter a vowel: ";
    std::cin >> userInput;

    // Checks to see if inputted data is A,E,I,O,U,Y
    if ((userInput == 'a')||(userInput == 'A')||(userInput == 'e')||
        (userInput == 'E')||(userInput == 'i')||(userInput == 'I')||
        (userInput == 'o')||(userInput == 'O')||(userInput == 'u')||
        (userInput == 'U')||(userInput == 'y')||(userInput == 'Y'))
    {
        std::cout <<"\nCorrect, "<< userInput <<" is a vowel!"<< std::endl;
    }
    else
    {
        std::cout <<"\nSorry, "<< userInput <<" is not a vowel"<< std::endl;
    }
    return 0;
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
				
						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 4, 2012
//    Updated: Feb 8, 2021
//    Taken From: http://programmingnotes.org/
//    File:  vowel.cpp
//    Description: Demonstrates checking if a char variable is a vowel
// ============================================================================
#include <iostream>
int main()
{
    // Declare empty variable
    char userInput = ' ';
 
    std::cout << "Please enter a vowel: ";
    std::cin >> userInput;
 
    // Checks to see if inputted data is A,E,I,O,U,Y
    if ((userInput == 'a')||(userInput == 'A')||(userInput == 'e')||
        (userInput == 'E')||(userInput == 'i')||(userInput == 'I')||
        (userInput == 'o')||(userInput == 'O')||(userInput == 'u')||
        (userInput == 'U')||(userInput == 'y')||(userInput == 'Y'))
    {
        std::cout <<"\nCorrect, "<< userInput <<" is a vowel!"<< std::endl;
    }
    else
    {
        std::cout <<"\nSorry, "<< userInput <<" is not a vowel"<< std::endl;
    }
    return 0;
}// http://programmingnotes.org/

This program should be very straight forward, and its basically checking to see if the user inputted data is the letter A, E, I, O, U or Y.

The resulting code should give the following output

Please enter a vowel: O Correct, O is a vowel!

==== HELLO WORLD v2 ====

This last example will demonstrate using the string data type to print the line “Hello World!” to the screen.





		
		
			Hello World - String Version
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 4, 2012
//    Updated: Feb 8, 2021
//    Taken From: http://programmingnotes.org/
//    File:  string.cpp
//    Description: Demonstrates using string variables
// ============================================================================
#include <iostream>
#include <string>
int main()
{
    // Declare empty variable
    std::string userInput = " ";

    std::cout << "Please enter a sentence: ";
    std::getline(std::cin, userInput);

    std::cout << "\nYou Entered: "<<userInput << std::endl;
    return 0;
}// http://programmingnotes.com
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
				
						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jan 4, 2012
//    Updated: Feb 8, 2021
//    Taken From: http://programmingnotes.org/
//    File:  string.cpp
//    Description: Demonstrates using string variables
// ============================================================================
#include <iostream>
#include <string>
int main()
{
    // Declare empty variable
    std::string userInput = " ";
 
    std::cout << "Please enter a sentence: ";
    std::getline(std::cin, userInput);
 
    std::cout << "\nYou Entered: "<<userInput << std::endl;
    return 0;
}// http://programmingnotes.com

Notice in line 10 we have to add “#include string” in order to use the getline function, which is used on line 17. Rather than just simply using the “cin” function, we used the getline function instead to read in data. That is because cin is unable to read entire sentences as input. So in line 17, the following code reads a line from the user input until a newline is entered.

The resulting code should give following output

Please enter a sentence: Hello World! You Entered: Hello World!

Tag Archives: char

Python || Using If Statements & String Variables

C++ || Convert Numbers To Words Using A Switch Statement

C++ || Char Array – Determine If A String Is A Number Or Not

C++ || Snippet – How To Read & Write Data From A User Specified Text File

C++ || Class & Input/Output – Display The Contents Of A User Specified Text File To The Screen

C++ || Char Array – Palindrome Checker Using A Character Array, ToUpper, Strlen, Strcpy, & Strcmp

C++ || Char Array – Convert Text Contained In A Character Array From Lower To UPPERCASE

C++ || Using If Statements, Char & String Variables

Search

Compile Your Code Now

Translate Page

Popular Pages

Recent

Archives

Categories